Early-diverging bumblebees from across the roof of the world: the high-mountain subgenus Mendacibombus revised from species’ gene coalescents and morphology (Hymenoptera, Apidae)
Author
Williams, Paul H.
Author
Huang, Jiaxing
Author
Rasmont, Pierre
Author
An, Jiandong
text
Zootaxa
2016
4204
1
1
72
journal article
10.11646/zootaxa.4204.1.1
3f8866d2-529e-43ad-b971-29fc52a13858
1175-5326
192302
C050058A-774D-49C0-93F9-7A055B51C2A0
3.
Bombus convexus
Wang
(
Figs 2
,
26
,
39, 41
,
58
)
<
Bombus
>
lugubris
Morawitz 1880
:339
(not of
Kriechbaumer 1870
:159, =
B. barbutellus
(Kirby)
s. l.
), type-locality citation ‘Gan-su’.
Holotype
worker by monotypy
ZISP
examined, (
Cyrillic
) ‘[
Gansu
]’ (but probably actually
Qinghai
,
China
).
Synonymised
with
Bombus convexus
Wang
by
Williams
(1991)
.
Note
1.
Bombus lugubris
Morawitz; Morawitz 1881
:243
;
Wu 1941
:281
.
Mendacibombus lugubris
(Morawitz)
;
Skorikov 1923
:149
;
Skorikov, 1931
:213
.
Bombus (Mendacibombus) lugubris
Morawitz
;
Bischoff 1936
:17
;
Panfilov 1957
:235
;
Tkalců 1961
:369
.
Bombus (Mendacibombus) convexus
Wang, 1979:190
, type-locality citation (Chinese) ‘[
Xizang
: Markam]’.
Holotype
queen by original designation
IZB
examined, (
Chinese
) ‘[
Markam
]’ (
Xizang
,
China
).
Bombus (Mendacibombus) convexus
Wang; S.-F. Wang 1982
:429
;
Yao & Wang 2005
:890
;
P.H. Williams 1991
:42
; S.-
F. Wang 1992
:1424
;
P.H. Williams 1998
:100
;
P.H. Williams 2004
:no. 26;
Cameron
et al.
2007
:165
; P.H.
Williams
et al.
2009
:130
; An
et al.
2011:5;
An
et al.
2014
.
Note 1 (
lugubris
). The original publication specifies that there was only one type (worker) specimen of the taxon
lugubris
Morawitz
, so the worker in the ZISP collection is regarded as the holotype by monotypy (
ICZN, 1999: Article 73.1.2
).
Etymology.
The species is named from the Latin
convexus
for ‘rounded’, a reference to a pronounced convexity or rounded posterior projection of the median posterior edge of metasomal T
2 in
the original description.
Taxonomy and variation.
This species shows effectively a single colour pattern of the hair with little variation. This is the pattern in the original description, which is unique within the subgenus. All specimens have a white-banded and none has a yellow-banded colour pattern. The form of the female median posterior edge of T2 (although slightly variable) and of the male genitalia are diagnostic.
Diagnostic description.
Wings nearly clear. Hair long, uneven and sparse.
Female hair colour pattern:
generally black, but with white hair intermixed especially as short hairs on the face, intermixed in a transverse band anteriorly on the thoracic dorsum and extending laterally and ventrally without black hairs to the midleg base, in a lateral patch posteriorly on the thoracic dorsum (lateral patch on the scutellum, metanotum, and propodeum, so that the thoracic dorsum between the wing bases has the hair entirely black), on T1 and anteriorly on T2, and intermixed on T4‒6 (
cf
. all other
Mendacibombus
species). Hindleg tibia with the corbicular fringes black, often with a few hairs with orange or white tips.
Female morphology:
labrum with the basal depression narrow, the transverse ridge moderately broad and high, medially not subsiding or interrupted and in the median third with scattered large punctures, lateral tubercles with a few scattered small punctures. T2 usually with a posteriorlydirected convexity of its median posterior edge, affecting a quarter of its breadth, especially pronounced in queens, for which there may be edge concavities and even slight pre-marginal depressions lateral to the convexity.
Male morphology
: beard of the mandible long, dense and black, but the short hairs and a few of the long hairs brown; T2 and sometimes T3 with posteriorly-directed convexities of their median posterior edge, affecting a quarter or less of their breadth. Genitalia (
Fig. 26
) with the volsella at its broadest near the midpoint of its length, the dorsal surface just distal to this point with a raised curved ridge, often with small teeth, just inside the inner margin, running for 0.3× the remaining distal length of the volsella; volsella distally sharply acute (pointed) and curled back dorsally and anteriorly. Gonostylus length 2× its greatest breadth. Penis-valve head length 0.25× the length of the penis valve distal to the broadest point of the spatha.
Material examined
. 6 queens
296 workers
51 males
, from
China
(
Fig. 58
:
AMNH
,
IAR
,
IZB
,
NHM
, PW, SC,
USNM
, YT,
ZISP
, ZX), with
6 specimens
sequenced (interpretable sequences listed in
Figs. 11–13
).
Habitat and distribution
. Flower-rich alpine and subalpine grassland, at elevations 2196‒(3449)‒
4500 m
a.s.l.. A species of the east Qinghai-Tibetan plateau, in the east Himalayan, Hengduan, and Qinghai-Gansu mountains, including the Min Shan and Qilian Shan. Compared to
B. waltoni
, distributions of the two species overlap broadly, but
B. convexus
extends less far to the north and west and tends to occur at lower elevation (and the two species rarely occur together at a site).
Bombus convexus
replaces the western
B. avinoviellus
in the lower alpine zone and upper forest wet meadows of the eastern Himalaya, where it appears to be rare. Regional distribution maps are available for
Sichuan
(P.H.
Williams
et al.
2009
) and
Gansu
(An
et al.
2011;
An
et al.
2014
).
Food plants
.
Williams
et al
. (2009)
, An
et al
. (2011; 2014).
Behaviour
. Mate-searching males perch on bare patches of ground and pursue other bees that fly past before the males return to the same perch (PW:
Fig. 2
,
29
.viii.
2009
, 3339 m
Diebu
,
Gansu
,
China
).